Radio frequency suppression capacitors have many applications in automotive vehicles. Such capacitors have many configurations, but basically comprise a capacitor winding sealed within a capacitor housing and having contact blades or leads extending out of the housing for connection into the circuit into which the capacitor is to be employed.
Copending application Ser. No. 912,557, filed June 5, 1978, describes a capacitor of the type including a capacitor winding mounted within a molded housing in which a pronged terminal is utilized for making plug-in type installations and other contact portions passing out of the housing from contact with the capacitor winding. As described in detail in that application, the durability during in-service use of the capacitor is greatly enhanced by a molding technique wherein the capacitor cavity and the contact portions adjacent the cavity are overlain with a molded-in material. This insures a very effective and reliable sealing of the interior of the housing, important in the relatively harsh automotive application environment.
Such process also results in greatly reduced manufacturing costs over prior art approaches to this problem.
Some configurations of such capacitors include a contact spring tab, which extends at an upward inclination from the upper side of the molded housing. The presence of such spring tab has generally been regarded as requiring a separate molded cap to be assembled to the capacitor assembly with a sealing material or seam heating utilized in order to provide a sealing of the cap to the mating housing controls.
Such process results in significantly increased manufacturing costs, which is of great significance in the context of capacitors intended for automotive application due to the vast volume of production required. This also results in substantially increased incidence of failure due to imperfections occurring in the manufacturing process and also renders the capacitor assembly less resistant to weathering and high temperature conditions.
Accordingly, it is an object of the present invention to provide an improved molded capacitor assembly and method of manufacture thereof for capacitors of the general type including a molded plastic housing having a recess formed in the upper flanged surface thereof which recess is adapted to receive the molded capacitor windings and including capacitor terminals having end faces in contact with the end faces of the capacitor windings. The terminals have portions which extend to generally overlie the flanged upper surface of the molded housing with one of the terminals including an angled end portion which is adapted to provide a spring contact at installation, which the capacitor is provided with a molded top cap sealing the capacitor winding and recess as well as overlying a portion of the flanged housing portion to seal the capacitor assembly against the environment.
It is still a further object of the present invention to provide such method which is relatively simple and low in cost to implement such as to maintain the manufacturing cost of the assembly at a minimum.